In photographic light-sensitive materials which contain compounds capable of releasing diffusible dyes upon occurrence of the redox reaction induced by exposure and development of silver halides (called diffusible dye-releasing redox compounds, hereinafter referred to as DRR compounds), and which are developed with a black-and-white developing agent, such as phenidone, particularly in multilayer color photographic light-sensitive materials for a diffusion transfer process, the oxidized product of the developing agent resulting from development of silver halides should act only on the DRR compound which is in combination with said silver halides. Otherwise, color separation of color images becomes poor. For the purpose of preventing the oxidized product of a developing agent from diffusing into a DRR compound-containing layer which is not in combination with a silver halide emulsion layer, it is conventionally known that a layer containing one or more of reducing substances capable of reacting with an oxidized product of a developing agent, such as redox compounds, e.g., hydroquinone derivatives, is provided in photographic light-sensitive materials, as described, e.g., in Research Disclosure, Vol. 15, No. 15162 (November 1976).
On the other hand, since hydroquinone or a derivative thereof (i.e., a scavenger for an oxidized product of a developing agent) contained in an intermediate layer reduces and consumes an oxidized product of a developing agent which is produced as a function of development of an emulsion layer and is necessary for image formation, the proportion of the oxidized product of a developing agent which should react with a DRR compound to form a dye image is thus decreased. The extent of the reduction of the proportion of the oxidized product to be reacted varies in a complicated manner depending on the processing temperature and various other factors. Further, the intermediate layer also has indirect influences on the development of silver halides, and the extent of such influences also varies in a complicated manner depending upon the processing temperature and other factors. As a result, the processing temperature dependence of the image density is greatly influenced by the intermediate layer. Thus, it has been necessary to control the processing temperature dependence due to the use of an intermediate layer containing a scavenger, i.e., to develop a technique for extending a processing temperature latitude.
The inventors have already found that an intermediate layer containing dispersed particles integratedly comprising a hydroquinone mixture having a solidification point of 100.degree. C. or lower (i.e., a scavenger of a developing agent oxidation product) and a water-insoluble and organic solvent-soluble homopolymer or copolymer having a repeating unit containing a ##STR1## bond in its main chain or side chain is effective to improve color separation of color images and also to heighten the maximum density, as disclosed in U.S. Pat. No. 4,366,236. As a result of following-up investigations on controlling the activity of the intermediate layer, i.e., reactivity with the developing agent oxidized product, the inventors further found that:
(1) the activity of the intermediate layer can be controlled by changing the dispersed particle size. In other words, the smaller the particle size, the higher the activity, and vice versa;
(2) the activity of the intermediate layer can be controlled by the kind and amount of the high boiling solvent copresent with the scavenger compound in the dispersed particles; and
(3) the activity of the intermediate layer can be controlled by the kind and amount of the water-insoluble polymer copresent with the scavenger in the dispersed particles.
However, when the intermediate layer is composed of one kind of a dispersion, sufficient performance in terms of expansion of the processing temperature latitude could not be obtained even making use of the above-described findings.
Research Disclosure, Vol. 152, No. 15239 (December 1976) describes that processing temperature latitude can be improved by a specific combination of scavengers of didodecylhydroquinone and 4-amino-1-hydroxy-N-[.alpha.-2,4-di-t-amylphenoxybutyl]-2-naphthamide. However, use of such a specific combination of scavengers gives rise to a problem in that the freedom in controlling the activity of the intermediate layer becomes quite narrow, because the activity of the intermediate layer is determined by the chemical structure of the scavengers.